1. Field of the Invention
Methods and apparatuses consistent with the present invention relate to wireless communication. More particularly, the present invention relates to a wireless communication method and apparatus using a high-frequency band.
2. Description of the Related Art
With the advent of wireless networks and increased demand for multimedia-data transmission, there is an increasing need for studies on effective transmission. Furthermore, the need for transmitting high-quality video such as DVD images and HDTV images between various home devices is increasing.
Currently, a technology standardization for transmitting mass-storage data in a wireless home network is in progress by a task group of IEEE 802.15.3c. This standard, called “mmWave” (Millimeter Wave), uses an electromagnetic waves having millimeter wavelengths (i.e., 30 GHz to 300 GHz) for transmission of data. This frequency band is an unlicensed band used by telecommunication operators, radio astronomy, and vehicle-collision prevention.
The carrier frequency of IEEE 802.11b and IEEE 802.11g is 2.4 GHz, and the channel bandwidth is approximately 20 MHz. Further, the carrier frequency of IEEE 802.11a and IEEE 802.11n is 5 GHz, and the channel bandwidth is approximately 20 MHz. In contrast, the mm Wave uses a carrier frequency of 60 GHz, and has a channel bandwidth of around 0.5 to 2.5 GHz. Hence, the mmWave has much higher frequencies and channel bandwidths than the conventional IEEE 802.11 line standards. Likewise, by using high-frequency signals having millimeter wavelengths, a very high transmission rate of several Gbps units can be expressed, and the size of an antenna can be made less than 1.5 mm, thereby implementing a single chip that includes an antenna.
Especially, research on the transmission of uncompressed audio or video data (hereinafter, called “uncompressed AV data”) between wireless devices using the high bandwidth of a millimeter wave are in progress. Compressed AV data is compressed with loss in a way that removes the parts less sensitive to the senses of sight and hearing through the processes such as motion compensation, DCT conversion, and variable-length encoding. Hence, the image quality can deteriorate due to loss in the compressed AV data, and the AV data compression between the transmitting device and the receiving device, and the restoration process must follow the same standard, which causes problems. In contrast, because uncompressed AV data includes digital values (e.g., R, G, and B elements) that represent pixel elements, high-quality images can be provided, which is advantageous.
Likewise, because large amounts of data are transmitted in high-frequency wireless communication, it is important to reduce the waste of wireless resources. Hence, there is a need for a technology that can reduce the bandwidth waste in high-frequency wireless communication.